The present invention relates to a dental-filling material formed of a gold-alloy powder and which can also include an organic binder, to be introduced into tooth cavities using the gold-condensation procedure. In another respect, the present invention relates to a method for preparing this dental-filling material.
The filling of dental cavities with so-called condensed gold is one of the oldest known procedures for filling cavities in teeth. According to this known technology, chemically pure gold in the form of foils, powder or sponge is introduced into the cavity and fastened to it mechanically. In the compacted state, condensed gold has a hardness of about 25 HV which, after being processed by additional cold compaction techniques can be raised to 30 to 50 HV. However, these values are subject to strong local variations depending on the kind of processing, namely, the sort of condensation applied and the various durations of condensation steps. Moreover, because of the temperature effects within the mouth, there is a slow drop-off in the cold compaction. Conventional condensed gold fillings therefore are not well suited for use in situations where it is expected that the filling will be subjected to strong stresses.
In the prior art, German OLS 34 03 779 discloses a dental-filling material for gold condensation purposes consisting of flake gold powder and of a plastic, organic binder liquefying at 20.degree. to 45.degree. C., in particular polyethylene glycol. This material is compacted ultrasonically. The hardnesses so achieved by this known technology, however, are only in the range of 40 HV. The broad application of gold alloys for condensing gold in the dental field is known from the German OLS 30 42 008.